The research aim was to investigate the appropriate ratio of sweet potatoe and red rice bran in the composite flour for producing Chinese steamed buns. The experiment was conducted in laboratory and arranged with Completely Randomized Design of single factor of the sweet potato and rice bran ratio ( f0 = 100% wheat flour, f1= 85% sweet potatote : 5% rice bran , f2 = 80% sweet potatote:10% rice bran, f3 =75% sweet potatote:15% rice bran, f4 =70% sweet potatote :20% rice bran, and f5=65% sweet potatote:25% rice bran. The parameter included moisture, ash and fat content, colour and bread loaf volume, flavor, aroma, colors and texture (hedonic and scoring). Data was analysed with analyses of variance and post hoc test with Duncan's Multiple Range Test (DMRT) at five percent of level of significancy. The result showed that the ratio of sweet potato and red rice bran in composite flour affected on the moisture, ash, and fat content, colour, loaf volume, , flavor, aroma, and texture of the steamed buns. The ratio of 85% sweet potato and 5% rice bran in composite flour produced the best quality of the steamed buns. The steamed buns had moisture, ash and fat content of 38.62%; 1.24% and 4.25% respectively and the L value, Hue and loaf volume were 61.42; 64.67 and 7.79% . In term of taste, the buns was slightly like and sweet by the panelist. On the other hand, the flavor of the buns had rice bran flavor, the colour was slightly purple and texture was softer compared to the buns with 100% wheat flour. Keywords : Chinese steamed buns, sweet potato, rice bran.